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The icing of wind turbine blade will seriously affect the power output of wind turbine and endanger the safe operation of wind turbine. Computational fluid dynamics (CFD) is used to study the icing characteristics of typical wind wing. Firstly, the impact characteristics of water droplets on NACA0012 type turbine under different attack angle of 0°,4°,8°are calculated. The calculated results are in good agreement with the experimental results, which shows that the calculation method is correct, and, the ice coating on the blade surface of typical wind turbine with different wind speed and temperature was simulated, and the variation trend of water collection coefficient and ice thickness with temperature and velocity was obtained. The results show that: 1) with the increase of wind speed, the ice thickness of blade surface increases and the icing adhesion area increases; 2) with the decrease of temperature, the ice thickness of blade surface increases; and 3) the anti-ice effect of S801 airfoil is obviously greater than that of S802 airfoil. The research result helps logically select turbine under low temperature conditions, providing reference for lowering the blade icing hazard.

The paper analyzes the advantages and disadvantages of two different energy management strategies which are the management strategy based on the dynamic system running state and the management strategy based on the driving cycle. The paper focuses on the study of the strategy based on the driving cycle, and points out that though the operation process of the global optimization strategy based on the driving cycle takes long and large amount of calculation so that it can hardly be used in the real vehicle. The strategy can be taken as the reference for the ideal optimization control target. In order to achieve the real-time optimal control, there are mainly the method based on the driving cycle of recognition control strategy and the method based on model predictive control, etc. It makes the exploration to predict the real-time optimal control strategy based on the driving cycle become real, and the effects of the control results get close to the offline global optimization. The proposed strategy is a new research hotspot and research trend of energy management strategy.

When the wind turbine blades are running under normal conditions, the blades will vibrate due to periodic aerodynamic forces, and the use time of blades will be reduced. In order to study the vibration characteristics of wind turbine blades, this paper selects 5 operating conditions (wind speed range from 15 m/s to 40 m/s) under different wind speed conditions. The CFD method is used to simulate the NREL PHASE VI blade, and the vibration and vibration displacement curves under different wind speeds are obtained. The results show that: 1) the main vibration modes of the blade are waving and shimmy, and the high order blade vibration modes have complex deformation of bending and torsion. 2) When the inlet velocity increases from 15 m/s to 40 m/s, the uneven distribution of pressure distribution on suction surface is increasing, and the maximum pressure difference is about 3 000 Pa when the inlet velocity is 40 m/s. 3) when the flow velocity is 15 m/s, the minimum amplitude is 0.525 4 mm, and when the flow velocity is 40 m/s, the vibration reaches the maximum of 3.628 2 mm, which is about 6.9 times of the minimum amplitude. The vibration curves of the 5 operating conditions are all attenuated trend and the blades tend to stabilize vibration, and when the wind speed is larger, the aerodynamic force generated by the wind flow has a greater force on the blade, and the amplitude of the blade tends to increase. The results of this study can provide a reference for the design of wind turbines.

In order to promote the in-depth development of simulation research of biofuel application , the development of the chemical reaction mechanism of biofuel combustion was explained, and application of Computational Fluid Dynamics Model in Combustion Simulation of Internal Combustion Engines were also explored. The technical idea of biofuel combustion mechanism construction and simplification was analyzed.The research progress of biofuel combustion simulation based on CFD combustion model was explored.By calling the biofuel combustion mechanism,Study on the combustion process and emission generation law of internal combustion engine was effective.The review showed that the chemical kinetics of biofuel combustion can be generated by the coupling and simplification of a typical single component combustion mechanism.By calling this synthesis mechanism,the combustion process analysis and emission generation analysis of biofuel.can be realized.Research showed that simulation research was an important technical approach to achieve biofuel application research.

Based on the energy storage problems for solar energy utilization and the advantages of spiral groove tube heat exchanger, spiral groove tubes are used in the solar energy phase change heat storage, with numerical simulation of the thermal storage process of heat reservoir. Firstly, the simulation method and the reliability of the used model are verified experimentally with smooth tube. Using spiral groove tube as water flow pipe and phase change material as heat storage medium, building the three-dimensional model by Gambit software and meshing by ICEM, the heat storage process in the spiral groove tube and smooth tube heat storage are numerically simulated while the heat transfer enhancing effect is investigated. The influence of structural parameters such as groove pitch and groove depth on the heat storage process is simulated numerically and the influence rules are analyzed. The results show that the convective heat transfer intensity and heat transfer capability are enhanced when the smooth tubes are substituted by spiral groove tubes in the phase change heat storage and the heat storage time become shorter. In the range of simulation, the optimal structural parameters of spiral groove tube is that the groove pitch p=7 mm and groove depth e=0.4 mm. The further improved design of phase change thermal storage can be realized in later research in-depth.

In order to improve the compatibility between inorganic semiconductor and organic polymer semiconductor, and optimize the photoelectric performance of the battery, a hybrid solar cell of TiO2/PCPDTBT based on one dimensional inorganic TiO2 nanorods ordered arrays and organic polymer PCPDTBT is constructed. The heterojunction interface properties between the inorganic and organic materials are controlled by amphiphilic organic triphenylamine-type molecules. The properties of the hybrid films are characterized by scanning electron microscope (SEM), transmission electron microscope (TEM), X-ray diffraction (XRD), energy dispersive spectrometer (EDS), UV-vis spectra (UV-vis), photoluminescence spectroscopy (PL), etc.. The battery performance tests demonstrate that the photovoltaic performance of the modified cell is improved, and the power conversion efficiency η is of 0.81%. Open circuit voltage decay tests demonstrate that the electron lifetime is increased after heterojunction surface/interfacial modification. These results indicate that the amelioration of morphology and structure of the active layer plays an important role on solar cell performance, by means of modification of the heterojunction surface/interface.

The heat storage process of the high temperature thermal energy storage container using single-stage PCM for solar thermal power generation is numerically simulated. The change curves of the PCM's temperature and liquid rate over time during the single-stage thermal stage melting process and its cloud distributions of the liquid rate at different time have been obtained. Through the analysis of the curves and cloud figures, in the premise of ensuring the heat accumulation amount, three kinds of PCM cascade regenerative high temperature thermal energy storage container design schemes are derived and simulated on their regenerative performance. The result indicates that the cascade heat storage schemes greatly reduce the total heat storage time and the "dead zones" effects effectively on the performance of heat storage during the single-stage regenerative terminal stage, which can make the PCM liquid rate distribution to be more uniform. It provides the theoretical basis for the optimization design of the high temperature phase change thermal energy storage container for solar thermal power generation applications.

The issue of the aerodynamic noises from wind turbine blades affecting the surrounding residents life begins to attract researcher's attention. Most of the existing researches are based on CFD software or experimental data fitting method to analyze the aerodynamic noises, so it is difficult to adapt the demand to dynamic analysis of the aerodynamic noises from wind speed variation. In this paper, the operation parameters, the inflow wind speed and the receiver location are considered, and a modified model to calculate aerodynamic noises from wind turbine blades which is based on traditional acoustic formulas is established. The program to calculate the aerodynamic noises from the 2 MW wind turbine blades is compiled using a time-domain analysis method based on the Simulink modular in Matlab software. And the pressure time sequence diagrams of the aerodynamic noises from wind turbine blades are drawn. It has provided a theoretical foundation to develop low noise wind turbine blades.